



 
Hi Jim, $10^x$ where $x$ is a positive integer is the number obtained by multiplying 10 by itself $x$ times. If you can't type exponents $10^x$ is often written 10^x. Hence for example
Hence better than one part in $10^9$ is better than one part in a billion. Write back if this is not what you needed, Jim wrote back
Hi again Jim, Sorry I misinterpreted your question. I have been looking for an example. I looked on the internet and found a site which claims to give the diamond to ore ratio in diamond mines. Their claim is that there is approximately 1 carat of diamond in 7.35 tons of ore. 1 carat is 0.2 grams and 7.35 tons is 6,667.81 kilograms (I asked Google). Hence there is approximately $5 \times 0.2 = 1$ gram of diamond in $5 \times 6,667.81 = 33,339,050$ grams of ore. That's approximately 1 gram in $3.3 \times 10^8$ grams of ore. Finally if I was trying to convince you to buy stock in a diamond mine I might have success if I can say "My mine's yield in weight of diamond in its ore is better than 1 part in $3.0 \times 10^{8}.$" I hope this helps, 



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